Malicious communications are coming from an increasing number of sources using ever changing techniques. These malicious communications present problems in terms of security breaches, such as providing access to internal documents, and resource consumption, such as flooding a network with useless traffic. One way in which these malicious communications get past a company's or user's security measures is by hiding the malicious code in attachments to the communication. Typical security measures simply look at the file extension of any attachment to determine whether or not to block communication. This allows the sender to circumvent these security measures by giving their malicious code a safe extension, or by hiding it within a different file type.